Method of making a transducer with a conductive magnetic layer

ABSTRACT

A transducer includes a first layer that is selectively deposited in a contact region to form a core, and selectively deposited in a transducer region to form a first element of the transducer. The transducer includes an electrically conductive magnetic deposit. The electrically conductive magnetic deposit forms a sidewall on the core. The electrically conductive magnetic deposit forms a second element of the transducer in the transducer region. The second element of the transducer has a planarized surface that is coplanar with a planarized surface of the sidewall.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a divisional of and claims priority of U.S.patent application Ser. No. 11/344,398, filed Jan. 31, 2006, the contentof which is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to transducer devices thatinclude an electrically conductive magnetic layer, and more particularlybut not by limitation to read/write heads that include an electricallyconductive magnetic layer.

BACKGROUND OF THE INVENTION

Read/write heads are typically formed in multiple thin film layers thatare deposited on a slider substrate. The transducer connectselectrically to an external circuit via contact pads. The contact padsare electrically connected to read and write transducers in theread/write head by way of traces in conductive layers and vias that passthrough insulating layers. Providing a via through an insulating layerrequires multiple process steps that are expensive and time consuming,and increase the possibility of a complete batch of read/write headsbeing scrapped due to an error in one of the process steps that areadded to produce the via.

A method and device are needed in which additional process steps neededto form a via are reduced. Embodiments of the present invention providesolutions to these and other problems, and offer other advantages overthe prior art.

SUMMARY OF THE INVENTION

Disclosed are transducers and methods of making transducers. Thetransducer comprises a first layer. The first layer is selectivelydeposited in a contact region to form a core. The first layer isselectively deposited in a transducer region to form a first element ofthe transducer.

The transducer comprises an electrically conductive magnetic deposit.The electrically conductive magnetic deposit forms a sidewall on thecore. The electrically conductive magnetic deposit forms a secondelement of the transducer in the transducer region. The second elementof the transducer has a planarized surface that is coplanar with aplanarized surface of the sidewall.

Other features and benefits that characterize embodiments of the presentinvention will be apparent upon reading the following detaileddescription and review of the associated drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a disc drive.

FIGS. 2-6 illustrate steps in providing a planarized sidewall on a coreand a planarized element of a transducer that are portions of a depositof an electrically conductive magnetic layer.

FIGS. 7-8 illustrate steps in forming a read/write head that includes aplanarized sidewall on a core and a planarized element of a transducerthat are portions of a deposit of an electrically conductive magneticlayer.

FIG. 9 illustrates a cross-sectional view of a read/write head thatincludes a planarized sidewall on a core and a planarized element of atransducer that are portions of a deposit of an electrically conductivemagnetic layer in the read/write head.

FIGS. 10-14 illustrate cross-sectional view of cores and cylindricalsidewalls.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

In the embodiments described below, a transducer is disclosed thatincludes an element of the transducer that is formed by deposition of anelectrically conductive magnetic layer. The deposition step that is usedto form the element of the transducer is also used to form a sidewall ona insulating core. The sidewall functions as a via and provides afeedthrough that is formed in an electrically conductive magnetic layer.Transducer signals are conducted between a transducer and contact padsby the core and associated circuit traces formed in conductive layers. Areliable feedthrough is provided with a simplified manufacturing processthat reduces the process steps needed to produce the transducer. Theprocess is especially beneficial in manufacturing read/write heads wherethere are a large number of feedthroughs needs in a restricted space.

FIG. 1 is an isometric view of a disc drive 100 in which embodiments ofthe present invention are useful. Disc drive 100 includes a housing witha base 102 and a top cover (not shown). Disc drive 100 further includesa disc pack 106, which is mounted on a spindle motor (not shown) by adisc clamp 108. Disc pack 106 includes a plurality of individual discs,which are mounted for co-rotation about central axis 109. Each discsurface has an associated disc head slider 110 which is mounted to discdrive 100 for communication with the disc surface. In the example shownin FIG. 1, sliders 110 are supported by suspensions 112 which are inturn attached to track accessing arms 114 of an actuator 116. Theactuator shown in FIG. 1 is of the type known as a rotary moving coilactuator and includes a voice coil motor (VCM), shown generally at 118.Voice coil motor 118 rotates actuator 116 with its attached heads 110about a pivot shaft 120 to position heads 110 over a desired data trackalong an arcuate path 122 between a disc inner diameter 124 and a discouter diameter 126. Voice coil motor 118 is driven by servo electronics130 based on signals generated by heads 110 and a host computer (notshown).

FIGS. 2-6 illustrate exemplary processes and structures that can be usedin order to provide sidewall conduction through an electricallyconductive magnetic layer. The process and structures are useful formagnetic data transducer, magnetooptic data transducers as well as othertransducers that include a conductive magnetic layer. The term “core” asused in this application refers to a support core, as shown for examplein FIGS. 2-7, 9-14, and does not refer to a magnetic core.

FIG. 2 illustrates a conductive layer 202 which is selectively depositedover an underlying substrate (not illustrated). The conductive layer 202extends over portions of a transducer region 204 and a contact region206. Using a selective deposition process such as photolithography, afirst portion 208 of the conductive layer 202 in the transducer region204 is not contiguous with a contact portion 210 of the conductive layer202 in the contact region 206. The contact portion 210 is thuselectrically isolated from the first portion 208, and the contactportion 210 can be used to carry a transducer signal without interferingwith functioning of the first portion 208 in a magnetic transducer.

A first layer 214 is deposited adjacent the conductive layer 202. Thefirst layer 214 is selectively deposited to form separate portions thatare not contiguous with one another. The first layer 214 includes a core216 in the contact region 206. The core 216 preferably has a shape of acylinder and has a distal end that protrudes.

The first layer 214 also includes a first element of the transducer 218in the transducer region 204. The first element of the transducer 218preferably comprises a spacer layer in a magnetic transducer formed inthe transducer region 204. The first layer 214 is preferably formed ofsilicon carbide, alumina, silicon dioxide or silicon nitride. Otherelectrically insulating materials used in magnetic transducers can alsobe used in the first layer 214.

FIG. 3 illustrates application of a mask 220. The mask 220 is patternedusing lithographic techniques to cover some portions of layers 202, 214,and to leave other portions of layers 202, 214 uncovered. The mask 220has an opening 224 that surrounds the core 216. There is a space 222between the mask 220 and the core 216, such that a portion of thecontact portion 210 is exposed inside the mask 220 that surrounds thecore 216. There is also a mask opening 226 in the transducer region 204.When the application of the mask 220 is complete, the mask opening 226in the sensor region 204 defines a location for deposition of a secondelement of the transducer (not shown in FIG. 3). When the application ofthe mask 220 is complete, the opening 224 defines a location fordeposition of a sidewall (not illustrated in FIG. 3) adjacent the core216. The mask 220 preferably has a thickness that exceeds the expectedthickness of the second element of the transducer.

FIG. 4 illustrates depositing of an electrically conductive magneticlayer 230 through the openings 224, 226 in the mask 220. Theelectrically conductive magnetic layer 230 is deposited in the space 222around the core 216 to form a sidewall 232 and a cap 236 on the core216. The sidewall 232 provides an electrical conduction path between thecontact portion 210 and subsequently deposited layers (not illustratedin FIG. 4). The sidewall 232 preferably conducts a transducer signal.The electrically conductive magnetic layer 230 is preferably a platedlayer. The electrically conductive magnetic layer 230 can include anseed layer to facilitate plating. The electrically conductive magneticlayer 230 preferably comprises a soft, high permeability magnetic alloythat includes nickel and iron. The sidewall 230 comprises a cylindricalshape that forms an electrically conductive path adjacent the core 216.The sidewall can have other deposition features in addition to thecylindrical shape adjacent the core 216.

The electrically conductive magnetic layer 230 is deposited through themask opening 226 to form a second element of the transducer 234. Thesecond element of the transducer 234 provides a magnetic transducerelement that is part of a transducer formed in the transducer region204. The second element of the transducer 234 preferably comprises amagnetic return layer in a magnetic transducer.

FIG. 5 illustrates application of a backfill layer 240 which backfillsthe sensor region 204, the contact region 206 and at least someintervening spaces between the sensor region 204 and the contact region206. The backfill layer 240 comprises electrically insulating material,preferably alumina. The layer 240 fills gaps between the second elementof the transducer 234 and the sidewall 232 and cap 236 in preparationfor planarization in a subsequent step described below in connectionwith FIG. 6.

FIG. 6 illustrates planarizing the sidewall 232, the cap 236 and thesecond element of the transducer 234 using a preferred method ofchemical mechanical polishing (CMP). Other known planarizing methods canalso be used. A polishing tool 250 is brought simultaneously in contactwith the sidewall 232, the cap 236, the second element of the transducer234 and the backfill layer 240. The tool 250 moves relative to the uppersensor surface 242 and polishes until there is a planarized upper sensorsurface 242 suitable for deposition of subsequent layers (notillustrated in FIG. 6). After planarizing is complete, the tool 250 isremoved and the upper sensor surface 242 is a planarized surface and isready for deposition of additional sensor layers in the sensor region204, and for deposition of additional contact layers in the contactregion 206. The planarizing process, whether done by chemical mechanicalpolishing or other planarizing methods, exposes upper surfaces of thesidewall 232 and the cap 236 so that further metallic contact structurescan be deposited. After planarization, the sidewall 232 protrudes to alevel that is substantially the same as a level of protrusion of thesecond element of the transducer 242. The protrusions of the sidewall232 and the second element of the transducer 242 have mutually coplanarplanarized surfaces. The term “coplanar” means that surfaces lie in thesame plane within the limits of the planarization process. When chemicalmechanical polishing is used, the coplanar planarized surfaces comprisechemical mechanical polished surfaces.

FIGS. 7-8 illustrate process steps in forming a transducer thatcomprises a read/write head that can be used in a data storage devicesuch as a disc drive. The views shown in FIGS. 7-8 are plan views of atrailing side of the read/write head. The read/write head includes acontact region 302 and a transducer region 304. Subsequent to theprocess steps shown in FIGS. 7-8, the transducer is lapped to a lap line306, exposing layers of the read/write head at a bottom side forcommunicating (reading and writing) data to a disc. The process stepillustrated in plan view in FIG. 7 corresponds generally with theprocess step illustrated in cross-sectional view in FIG. 4. The processstep illustrated in plan view in FIG. 8 corresponds generally with theprocess step illustrated in cross-sectional view in FIG. 6 (afterremoval of the tool 250 from FIG. 6).

In FIG. 7, a topmost layer comprises a mask 310 (corresponding with themask 220 in FIG. 4). The mask 310 has an opening 312 that surrounds acore 314. There is a space 316 between the mask 310 and the core 314such that a ring-shaped portion 320 of a contact portion 318 is exposedbetween the mask 310 and the core 314. The contact portion 318 connectsto the transducer region by way of a trace 322 that is part of the samelayer as the contact portion 318. As illustrated, the read/write headtypically has multiple cores such as core 314 and multiple mask openingssuch as opening 312 which provide for multiple contacts in the contactregion 302. The contacts are typically used for making electricalconnections to transducer features such as a read head, a write head,electrical lap guides (ELG) and the like. One or more of such contactscan be made using the processes and structures disclosed here. Somecontacts can also be made using conventional processes when suchcontacts are made in layers that do not require the processes disclosedhere. The mask 310 also has an opening 330 that defines a location fordeposition of a second element of the transducer (not shown in FIG. 7).

In FIG. 8, the mask 310 has been removed, an electrically conductivemagnetic layer has been deposited, a backfill layer 340 is added, andthe exposed topmost surface is planarized, producing coplanar surfacesof multiple layers. A planarized surface of the electrically conductivemagnetic layer is exposed and comprises a sidewall 342, a cap 344, and asecond element of the transducer 346. The sidewall 342, the cap 344 andthe second element of the transducer 346 have mutually coplanar surfacesthat are planarized. The backfill layer 340 is also planarized andcoplanar with the sidewall 342, the cap 344 and the second element ofthe transducer 346. It is understood by those skilled in the art thatthere are small differences in erosion rates for differing materialsduring the planarization process, and that extremely small elevationsdifferences can occur for different materials. The planarizationproduces coplanar surfaces within the limits of the planarizationprocess used. The sidewall 342 provides an electrical feedthrough (alsocalled a via) without the need for deposition of separate layers for thefeedthrough. The feedthrough is accomplishing using the electricallyconductive magnetic layer that is needed for the transducer. The cap 344is a preferred feature, but not required to complete the feedthroughfunction. The transducer illustrated in FIGS. 7-8 is thus generally madeaccording to the process steps described above in connection with FIGS.2-6.

FIG. 9 illustrates a transducer 400 that comprises a perpendicularread/write head that transduces data stored on a disc 402 in aperpendicular recording format. The head 400 moves in a direction 404relative to the disc 402. The transducer 400 includes a transducerregion 403 and a contact region 405. The head 400 has a trailing side406. The head 400 is separated from the disc 402 by an air bearing layer408. The head 400 comprises multiple layers that are deposited indesired patterns on a substrate 410 to form functional components of aread transducer 412, a write transducer 414 and multiple electricalconnections to electronic circuitry external to the head 400. Only onesuch electrical connection 416 is visible in the cross-sectionillustrated in FIG. 9. A lead 418 from an external electronic circuit isultrasonically bonded to a contact pad 420. The substrate 410 typicallycomprises AlTiC.

The read transducer 412 includes an upper shield 430 that is alithographically patterned first portion of a conductive layer(comparable to layer 202 in FIG. 2). The conductive layer also includesa lithographically patterned contact portion 432 that includes a trace(comparable to trace 322 of FIG. 7) that is an electrical transducerlead, typically a lead for a magnetoresistive sensor 434. An insulatinglayer (comparable to layer 214 in FIG. 2) is deposited on the conductivelayer 202 and is lithographically patterned to include a spacer layer436 in the transducer region 403, and a core 438 in a contact region405.

The write transducer 414 includes a magnetic return layer 440 that is alithographically patterned portion of an electrically conductivemagnetic layer. The electrically conductive magnetic layer also includesa lithographically patterned sidewall 442 and cap 444. A top (distal)surface of the electrically conductive magnetic layer is planarized(along with a backfill layer) to form a planar surface for deposition ofsubsequent layers of the write transducer 414. A metal deposit 450electrically connects the sidewall 442 to the external contact pad 420.Additional contacts can be provide for magnetoresistive read transducertraces, write transducer traces, electrical lap guide (ELG) traces orother transducer traces.

FIGS. 10-14 illustrate exemplary cores 600-604 and cylindrical sidewalls606-610. The sidewalls 606-610 can conform to a cylinder 606 that isround, a cylinder 607 that is oval, a cylinder 608 that is square, acylinder 609 that is rectangular, or a cylinder 610 with an irregularpath. The term cylinder refers to a surface generated by a line whichmoves parallel to a fixed line so as to cut a fixed plane curve todefine a cylinder along the line which moves.

It is to be understood that even though numerous characteristics andadvantages of various embodiments of the invention have been set forthin the foregoing description, together with details of the structure andfunction of various embodiments of the invention, this disclosure isillustrative only, and changes may be made in detail, especially inmatters of structure and arrangement of parts within the principles ofthe present invention to the full extent indicated by the broad generalmeaning of the terms in which the appended claims are expressed. Forexample, the particular elements may vary depending on the particularapplication for the transducer while maintaining substantially the samefunctionality without departing from the scope and spirit of the presentinvention. In addition, although a preferred embodiment described hereinis directed to a read/write head for disc drive, it will be appreciatedby those skilled in the art that the teachings of the present inventioncan be applied to other transducers that include magnetic functions,without departing from the scope and spirit of the present invention.

1. A process, comprising: depositing a first layer to form a supportcore in a contact region, the support core being electrically insulatingand having an outwardly facing support core sidewall that extends to asupport core top surface; and to form a first element of a transducer ina transducer region, the first element being non-contiguous with thesupport core; depositing an electrically conductive magnetic layer toform a first magnetic deposit portion that surrounds the support coresidewall and that extends over the support core top surface; and to forma second element of the transducer in the transducer region; andplanarizing the first magnetic deposit portion and the second element ofthe transducer.
 2. The process of claim 1, and the first magneticdeposit portion protruding to a level that is substantially the same asa level of protruding of the second element of the transducer after theplanarizing.
 3. The process of claim 1, wherein the planarizing formsmutually coplanar surfaces on the support core sidewall and the secondelement.
 4. The process of claim 1, wherein the planarizing compriseschemical mechanical polishing.
 5. The process of claim 1, furthercomprising: forming the first layer from a material selected from thegroup of: silicon carbide, alumina, silicon dioxide, silicon nitride. 6.The process of claim 1, further comprising: depositing an electricallyinsulating backfill layer in a space between the support core sidewalland the second element of the transducer.
 7. The process of claim 1,wherein the depositing of the electrically conductive magnetic layerfurther forms a cap on the support core top surface.
 8. A method,comprising: conducting a transducer signal to a contact portion of aconductive layer in a laminated magnetic transducer that has atransducer region and a contact region; depositing a first layer in thecontact region that forms a support core, and depositing the first layerin the transducer region that forms a first element of a transducer;depositing a conductive magnetic layer that conducts the transducersignal from the contact portion to a distal end of the support core, theelectrically conductive magnetic layer forming a second element of thetransducer in the transducer region; and planarizing the electricallyconductive magnetic layer.
 9. The method of claim 8, and the conductivemagnetic layer conducting the transducer signal to an external contactpad in the contact region.
 10. The method of claim 8, and amagnetoresistive element of the transducer generating the transducersignal.
 11. The method of claim 8, and conducting the transducer signalto a write transducer.
 12. The method of claim 8, and depositing a seedlayer prior to depositing the conductive magnetic layer.
 13. A process,comprising: depositing a first layer that forms a cylindrical supportcore in a contact region of a transducer, the support core beingelectrically insulating and having an outwardly facing support coresidewall that extends to a support core top surface; and that forms afirst element of a transducer, the first element being non-contiguouswith the support core; depositing an electrically conductive magneticlayer that forms a first magnetic deposit portion that surrounds thesupport core sidewall and that extends over the support core topsurface; and that forms a second element of the transducer on the firstelement; and planarizing the first magnetic deposit portion and thesecond element of the transducer.
 14. The method of claim 13, whereinthe depositing of the electrically conductive magnetic layer comprisesdepositing through openings in a mask.
 15. The method of claim 14,wherein the mask is patterned using a lithographic technique.
 16. Themethod of claim 13, wherein the depositing of the electricallyconductive magnetic layer comprises plating.
 17. The method of claim 16,wherein the plating comprises depositing a seed layer.
 18. The method ofclaim 13, and further comprising application of a backfill layer beforethe planarizing.
 19. The method of claim 18, wherein the backfill layercomprises electrically insulating material.
 20. The method of claim 13,wherein the first magnetic deposit and the second element are planarizedsimultaneously.